Judith Winters
Judith Winters was a human schoolgirl attending Coal Hill School in 1963. During the Shoreditch Incident, the Black Dalek of the Renegade Dalek faction enslaved her to a Dalek battle computer. Her mind and imagination were used to develop new stratagems against the rival Dalek faction, the Imperials. She operated the Renegades' time controller unit and had a mental link to the Black Dalek. When connected to the battle computer, she sat in a chair not unlike Davros' wheelchair and spoke in a Dalek-like voice.
Enhanced by the Renegades, she could also shoot lightning-like bursts of force from her hands, with which she killed the traitorous, both to the Royal Air Force and to the Renegades, Mike Smith and George Ratcliffe. (TV: Remembrance of the Daleks)
Judith was restored to normal when the Black Dalek destroyed himself. However, she never recovered mentally from her experiences and when Ace visited her over 25 years later, she remained a broken woman, living in a mental institution. (PROSE: In the Community) She was still in the asylum in 1999. (PROSE: The Suns of Caresh)
Behind the scenes
Judith Winters never had her name revealed on-screen. The credits for Remembrance of the Daleks credited her only as "The Girl". The name "Judith Winters" comes from the Brief Encounter story In the Community. Kate Orman wanted to name the character "Caroline Grey" and did so in a self-published online story entitled The Changeling.